Joint Subchannel Pairing and Power Control for Cognitive Radio Networks with Amplify-and-Forward Relaying

Algorithm 4

Suboptimal algorithm  2.

(1) Equally distribute the total power on each subchannel, that is, 𝑃^𝑠_𝑛,𝑚=𝑃_𝑆/𝑁,𝑃^𝑟_𝑛,𝑚=𝑃_𝑅/𝑁,∀𝑛∈𝐍,∀𝑚∈𝐍.

(2) Do optimal subchannel pairing by the Hungarian method.

(3) Check whether the constraints (3) and (4) are satisfied:

(4) if constraints (3) and (4) are satisfied then

(5) obtain the final solution, and the algorithm terminates;

(6) else if constraint (3) is violated but constraint (4) is satisfied then

(7) 𝑃_𝑆=𝑃_𝑆−Δ(Δ>0);

(8) else if constraint (3) is satisfied but constraint (4) is violated then

(9) 𝑃_𝑅=𝑃_𝑅−Δ;

(10) else if both constraints (3) and (4) are violated then

(11)  𝑃_𝑆=𝑃_𝑆−Δ,𝑃_𝑅=𝑃_𝑅−Δ;

(12) end if

(13) Go to step 1.